Selective adsorptive removal of anionic dyes from aqueous solutions using MIL-101@GO: Effect of GO

• Published in: Colloids and surfaces. A, Physicochemical and engineering aspects Physicochemical and engineering aspects, 2023-06, Vol.667, p.131364, Article 131364
• Main Authors: Cui, Guang-Yu, Zhang, Wei, Yang, Ji-Min
• Format: Article
• Language: English
• Subjects: Adsorption driving forces; MIL-101@GO; Pollutant dyes
• ISSN: 0927-7757; 1873-4359
• DOI: 10.1016/j.colsurfa.2023.131364

Metal−organic framework (MOF)@graphene oxide (GO) composite materials possess the advantages of both GO and MOFs, and thus, they can be employed as effective dye adsorbents. This paper proposes a simple strategy for the preparation of MIL-101 @GO composite materials to effectively adsorb anionic dyes (Congo red, o-cresolsulfonphthalein, methyl orange, and acid chrome blue K) by adding GO to MIL-101 to form a nano-packed structure. The maximum adsorption uptakes of MIL-101 @GO were 2734.9, 484.5, and 1762.8 mg g–1 for Congo red, o-cresolsulfonphthalein, and methyl orange, respectively. These values significantly exceed the corresponding values of the original MIL-101 because of additional factors that promoted adsorption, namely hydrogen bonding and the presence of agglomerate pores. Only the maximum adsorption uptake for acid chrome blue K was lower than that of MIL-101, because of steric hindrance. Our analysis showed that the adsorption behavior of MIL-101 @GO toward Congo red, o-cresolsulfonphthalein, and methyl orange is governed by a synergistic interplay of hydrogen bonding, electrostatic interactions, π–π interactions, the adsorption space, and agglomerate pores in the composite, whereas the adsorption behavior toward acid chrome blue K is mainly limited by steric hindrance. Understanding these interactions may contribute to the development of improved sustainable composite adsorbents. [Display omitted] •MIL-101@GO composites with agglomeration pore have been synthesized.•The composite showed good recyclability, with adsorption capacity retention as high as 90 % even after 5 recycling procedures.•MIL-101@GO composites have different adsorption uptakes towards anionic dyes due to the different adsorption droving forces.